Cross-border truck drivers are worried they will face heavy fines if they make mistakes using a mandatory electronic system for customs clearance that begins next month.

Customs is still using officers to handle declarations at all four land control points, but the system will go digital on November 17 under the new Road Cargo System.

One key difference is the new system will require shippers and drivers to submit details about their loads at least 30 minutes in advance, by internet or phone. Drivers currently make their declarations when they drive up to the customs window at the border crossings.

Drivers who do not make declarations in advance will have to wait 30 minutes before crossing. If they have nothing to declare, drivers must press an 'empty car' button at the border.

A failure to make a declaration, either by mistake or design, could result in a HK$10,000 fine. Drivers will be fined HK$2,000 if they fail to observe the 30-minute waiting period or forget to press the 'empty' button.

Stanley Chiang Chi-wai, chairman of the Lok Ma Chau China-Hong Kong Freight Association, said: 'We have reservations about this. Some drivers might miss some procedures when they are in a hurry. If they are fined for this, it will hurt the industry. Customs should be more flexible on this.'

Chiang agreed that in the long term the new system would increase the efficiency of border declarations. But the industry will have to find additional resources to handle the declarations, raising operating costs.

Chief Superintendent Ben Leung Lun-cheung, head of customs' land boundary command, said the HK$178 million system would shorten the time needed for clearance processing by two-thirds and help to save manpower at the border. Customs would further promote the new system and be flexible on penalties, he said.

It currently takes drivers about one minute to get cleared, stopping briefly at both immigration and customs control points. The new, automated system will take only 20 seconds and one stop, when drivers give readings of their fingerprint and identity cards, and submit their forms into a machine.

The system would also help customs catch smugglers, Leung said, by matching the details on declaration forms with customs' own database to aid spotting suspicious traders and trucks. Chiang acknowledged that this could protect drivers from shippers who try to manipulate them into smuggling cargo.

But in many cases, he said, truck drivers only learned the size of their shipment at the last moment, and they might not be able to declare it 30 minutes in advance.

Many drivers, he said, would want to avoid the cost of calling customs from the mainland, preferring to make the cheaper call when they arrived at the border crossing. This would cause heavy traffic at the border when they all had to wait 30 minutes.

The system has been on trial since May last year, but only 14 per cent of the daily 21,000 trucks crossing the border were using it, Leung said.